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The cartesian closed bicategory of generalised species of structures
, 2006
"... Abstract. The concept of generalised species of structures between small categories and, correspondingly, that of generalised analytic functor between presheaf categories are introduced. An operation of substitution for generalised species, which is the counterpart to the composition of generalised ..."
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Cited by 23 (3 self)
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Abstract. The concept of generalised species of structures between small categories and, correspondingly, that of generalised analytic functor between presheaf categories are introduced. An operation of substitution for generalised species, which is the counterpart to the composition of generalised analytic functors, is also put forward. These definitions encompass most notions of combinatorial species considered in the literature—including of course Joyal’s original notion—together with their associated substitution operation. Our first main result exhibits the substitution calculus of generalised species as arising from a Kleisli bicategory for a pseudocomonad on profunctors. Our second main result establishes that the bicategory of generalised species of structures is cartesian closed. 1.
A Basic Distributive Law
 JOURNAL OF PURE AND APPLIED ALGEBRA
, 2002
"... We pursue distributive laws between monads, particularly in the context of KZdoctrines, and show that a very basic distributive law has (constructively) completely distributive lattices for its algebras. Moreover, the resulting monad is shown to be also the double dualization monad (with respect ..."
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Cited by 16 (3 self)
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We pursue distributive laws between monads, particularly in the context of KZdoctrines, and show that a very basic distributive law has (constructively) completely distributive lattices for its algebras. Moreover, the resulting monad is shown to be also the double dualization monad (with respect to the subobject classifier) on ordered sets.
A Classification of Accessible Categories
 Max Kelly volume, J. Pure Appl. Alg
, 1996
"... For a suitable collection D of small categories, we define the Daccessible categories, generalizing the #accessible categories of Lair, Makkai, and Pare; here the ..."
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Cited by 16 (1 self)
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For a suitable collection D of small categories, we define the Daccessible categories, generalizing the #accessible categories of Lair, Makkai, and Pare; here the
How Algebraic Is Algebra?
, 2001
"... . The 2category VAR of finitary varieties is not varietal over CAT . We introduce the concept of an algebraically exact category and prove that the 2category ALG of all algebraically exact categories is an equational hull of VAR w.r.t. all operations with rank. Every algebraically exact category ..."
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Cited by 1 (0 self)
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. The 2category VAR of finitary varieties is not varietal over CAT . We introduce the concept of an algebraically exact category and prove that the 2category ALG of all algebraically exact categories is an equational hull of VAR w.r.t. all operations with rank. Every algebraically exact category K is complete, exact, and has filtered colimits which (a) commute with finite limits and (b) distribute over products; besides (c) regular epimorphisms in K are productstable. It is not known whether (a)  (c) characterize algebraic exactness. An equational hull of VAR w.r.t. all operations is also discussed. 1.
Higherdimensional Mac Lane's pentagon and Zamolodchikov equations
, 1999
"... An important ingredient of Mac Lane's coherence theorem for monoidal categories is Mac Lane's pentagon, a diagram whose commutativity is needed so that \all diagrams commute". This paper gives a higherdimensional generalization of Mac Lane's pentagon: a 6dimensional diagram who ..."
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An important ingredient of Mac Lane's coherence theorem for monoidal categories is Mac Lane's pentagon, a diagram whose commutativity is needed so that \all diagrams commute". This paper gives a higherdimensional generalization of Mac Lane's pentagon: a 6dimensional diagram whose commutativity is needed in order for all diagrams in somewhat weak teisi to commute. Looping twice gives a 4dimensional diagram in somewhat weak braided teisi, of which ve 3dimensional edges can be interpreted as proofs of ve dierent Zamolodchikov equations in braided monoidal 2categories. Hence higherdimensional Mac Lane's pentagon expresses the relations between these proofs concisely. 1 Introduction The coherence theorem for tricategories states that every tricategory is triequivalent to a Graycategory [6]. But there is also another coherence theorem for tricategories, stating that tricategories are (algebras for a) contractible (operad) [1], which roughly says that \all diagrams in a tricategory...
CATEGORICAL LOGIC AND PROOF THEORY EPSRC INDIVIDUAL GRANT REPORT – GR/R95975/01
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